Posted
by
ScuttleMonkey
on Monday October 10, 2005 @01:08PM
from the need-one-big-enough-to-sleep-on dept.

Sullivan writes "Maccentral is running a story on a startup called Splashpower that hopes to be able to wirelessly recharge all of our handheld devices. They have a working prototype that already recharges an iPod Mini and a cell phone. Now we can look forward to yet another way to get brain cancer."

I think this is a very cool device and have often wondered why more devices
haven't come with wireless re-chargability (think electric toothbrushes). But
I wonder about the efficiency of this method. Is it? And if it's not, how less
efficient is it than direct contact recharging? As more and more gadgets and devices
become rechargable technology this would seem to be more important. I don't know much
about electronics at the engineering level, so any erudite replies would be
appreciated.

Excellent link from the parent -- I have an electric toothbrush that charges the same way and I've always wondered how efficient it is. Apparently it isn't much worse than traditional adapters used for phones and such: about 70%.However, if you look at the photo [macworld.com] of the splashpower base, it looks as though the base itself uses an AC adapter (the cord appears to have a male DC-power connector). If that's the case then you really have to hits in the chain, and the system is ultimately 50% efficient (.7 f

Righto. Overall efficiency = E1 * E2. But you have to convert from AC (wall current) to DC since your device runs on DC, two conversions are necessary. At least here in the US, power is cheap so if this tech becomes cheap enough I think people will buy into it for the convenience.

Also, you're going to get less than.7 efficiency from the inductive recharger. The.7 efficiency on something like a toothbrush-charging stand assumes that the coils actually overlap slightly (know that little knob that the toothbrush rests on? It's actually part of the magnetic core that helps transmit the AC over). The electric field decreases with the square of distance. In one of those toothbrush chargers, the inductors are separated maybe by a millimeter of thin plastic. If you have... say a mousepad-sized recharging "station" to put all of your goodies onto, you might end up with distances of several inches from the charging coil to the pickup coil in the device you actually want to charge. Without having an actual "stand" like electric toothbrushes do, you aren't going to transmit much power. If you're going to have a stand, might as well have metal contacts, and forego the less efficient inductive method. The only reason why toothbrushes really do that is because they're often wet, and you put them in your mouth, so you wouldn't want metal contacts sticking out (my waterproof electric razor actually has metal contacts, you just wouldn't want to plug in the AC while it's wet).

I think that that might be AC current running into the pad. As I understand the system, it is the change inherent in the AC system that allows the inductive power to work. I am pretty sure that my toothbrush connects the 120AC to the coil in the charging base and then my toothbrush makes up the other half of the transformer that turns the power into something useful.

If it works like this, there would only be one conversion thats only slightly less efficient than the standard power adaptor. Also, most

Actually, Tesla wanted to be able to pull power at long range. The splash pad is just a two part transformer (the pad is one coil, and the clip-on adapter is the second coil). So, it turns the electricity from the wall into magnetic pulses which are then turned back into electricity (it's not very efficient, but who needs efficiency when you're being encouraged to be lazy anyways?).

Yeah, except Tesla would have used a couple of million volts, giving rise to massive bloody great bursts of lightning that have a nasty habbit of electrocuting passing cattle, and whose cracks of thunder *really* annoy the villagers ten miles down the valley...

You forgot "clean all of the lint and crud out of the charging port" and "wiggle phone around so the contacts make good contact rather than just barely missing" in your description of the old method. You also may have forgotton "make sure that cord is at such an angle so as to facilitate minimal breakage after grabbbing and walking away without remembering to unplug it in the morning".:)

You're that guy from the TV commercials, aren't you? You know, the guy for whom straining spaghetti or wiping off a table or opening a jar are so incredibly difficult and frustrating that you have to swipe all your existing products off a tabletop with both hands and buy some special device to do it for you.

No, but I am the guy who carries his cell phone in a pocket of jeans or coveralls, where the charging socket gets filled pu with lint and dust. Then again, I did buy a Eurosealer at Walgreens (mostly for humor value), and my tabletop could definitely use a sweeping-off-with-both-hands...:)

I agree with you to a point, but you forgot that you need the 5 cords for the 5 devices you have, with each one plugged into an outlet. So it would be convienent if you could just sit any of your devices on this and have them recharging. I mean, you set them somewhere, anyhow. Why not have them recharging each time you do so?

"I agree with you to a point, but you forgot that you need the 5 cords for the 5 devices you have, with each one plugged into an outlet."You are assuming that one pad will charge every device. It would be very possible to make a "standard" DC port for every device. Chargers would be universal and easy to use. Heck USB is very close right now.The problem is none of the companies want it. They all make good money off of selling extra chargers.

I suspect the lack of a DC standard has more to do with the lack of benefit, not necessarily the income from selling chargers. If you're the manufacturer of a DC-powered device today, you've already come to terms with the fact that you'll need to bundle an AC adapter with it. That's already going to be part of your cost. Since the selection of a DC voltage for your adapter impacts the ultimate cost of the adapter very little, the design of your device therefore drives the selection of a DC voltage. If y

What's missing is (a) the standard, and (b) the infrastructure, either in the form of power outlets in the wall (or inductive devices like this on your desk) and/or multi-port adapters optimized for that standard DC voltage.

You can sort of hack such a system together, using Radio Shack's adapt-a-plug system. You just need a plug that splits into two parallel plugs (like this [radioshack.com]), repeat as necessary (and a PSU with enough current capacity to power all the parallel devices, of course - you can buy wall warts

And, if it works how I think it does, it would already be universal since the voltage conversion is handled by the coil and circuitry in the device to be charged and is only being supplied an alternating current to make the magnetic fields induce current.

-iPod-GameBoy Advanced-her own cell phone-her own notebook (yes, I realize this part is overkill, but _you_ try telling a 16 year old girl she needs to leave it at home)... all of which required their own, seperate power brick for charging. I ended up taking a power strip with me to plug all of the rest into at the hotel so I wouldn't have them spread all over the room.

Splashpower Ltd., established as the result of a business competition at Cambridge University, has developed a wireless charging system that uses electromagnetic induction to accomplish wireless charging of devices.

That's me exactly. I absolutely hate having a power cord for my phone floating around in my car. I would love a pad built into the small holding tray (or whatever it could be called) that's in my center console. I already take my cell phone and PDA out of my pocket and place them there anyway, why not add effortless recharging to it?

You really don't need to hate the wires with a passion. All you need is for two ore more rechargable items to stay on to of. Right now in my house, I have a digital camera, 2 cell phones, two mp3 players, a PocketPC, Nintendo DS, and two laptops. Can you imagine what it'd look like to have all these chargers on one outlet? Having a pad you could just lay your rechargables

the way I understand it, it works in exactly the same way as the transformer in every power supply...
these things are short range (typically a few centemeters max) so the risk of em celular damage should be insigificant. I wonder though, how this will play with the actual electronics in the device itself. Electronics tend to get fried by high power e.m. fields, and if the device has any kind of coil that isn't intended for power coupling you may end up cooking the device?

"It's basically the concept of creating a magnetic field that goes parallel to the surface of the pad rather than out of the pad and this has many benefits," said Lily Cheng, chief executive officer and cofounder of the company, speaking at a news conference. "It enables us to deliver a very uniform output across the pad and enables us to make a receiver coil that is very thin."

Sounds like they are using a basic transformer here. Only difference is that they didn't build the two coils in one solid piece

I would not let this device anywhere near an iPod. It would bulk erase the hard drive

From what I have seen of bulk erasers, they tend to be, well, bulky among other things. Usually the coil wires are 2 or 3 mm thick with only a few dozen windings, and they charge up to release a whole lot of emf at once, consuming a kilowatt or so. This would be a much lower power device only consuming a few watts at most. Also, I think that hard drives can protect against some "lower power" emf. Otherwise you would

That's all very nice, but what I'd really like to see is power cords and adapters for my tech gear just made neater.

To power my mac and accessories I have twelve separate powercords and seven different adapters making a mess under my desk. Shouldn't it be possible to make a single adapter to power all the smaller devices, and have some neat way to daisy chain little power cords for the stuff that doesn't need much power (which is most of the devices on my desk)?

IMO, what we need is a single standard for power distribution that caters to the device, not dozens of adapters that are a slave to a single 120VAC standard.

Most small electric devices operate off of DC power, so no matter what, you have to have an adapter to convert AC power to DC. Since you have to have the adapter anyway, it doesn't really matter what DC voltage you go with, so you pick whatever's going to be cheapest for the situation. Consequently, we have all sorts of DC power requirements.

What might help the situation is for someone to come up with a standard for power outlets that use a standardized DC voltage in addition to AC. Or maybe a handful of voltages. Different contacts could provide your DC voltage(s), in conjunction with your AC voltage.

Device manufacturers could then target those standardized voltages and spend less money on adapters.

So, they have created a device that recharges devices wirelessly, if you place the device on top of the pad.

My cell phone, my beard trimmer, and my toothbrush already recharge wirelessly... sure, I have to place them in their cradles and line up the contacts, but it's still approximately the same.

What is being offered here is a universal charger system. The rest of it is bells and whistles. What Splashpower needs to do is get the device producers to incorporate the hardware necessary for this, and to get hotels etc. to install the pads.

This is problematic, as stated in the article. Device-makers won't install the charging coil unless the infrastructure for charging is in place; establishments won't purchase the charging pads unless a sufficient amount of devices have the coil installed. There's just no ROI for a hotel chain to install these in their rooms and suites, and no reason for an end-user to purchase an enabled device if chargers aren't available.

At the current price point, it isn't going to happen. If they can get a big player in peripherals and handhelds to sign on, they've got a chance -- as long as their unit price drops dramatically, which they allude to in the press release / article.

This idea has been worked over tons of times, and discarded as unprofitable. The difference here is the ability to charge multiple devices at once. Is it enough? Remains to be seen.

A big problem is that device manufacturers will need to incorporate two sep

If the company has enough capital, they could always go ahead and handle one end of the chicken/egg problem themselves. Lets say they deal with Nokia to pay for the installation of the receiver into every phone being sold by Nokia in Britain. Sure, they'll have to kick out $15 per phone, but lets say they sell a million phones... it's $15,000,000 to get a huge user base plus all the advertising that we assume they'll cram into the box.I'm not sure it's unfeasable, they'd just need to bankroll the beginnin

In your example, they'd need to pay for the other half of the deal. At $250 a pop, few consumers would spring for the charger -- unless the coil were imbedded in most of their devices. So multiply that figure by 3 or 4, to add the coil to other devices.

The flip side would be to pay for the chargers in public/common areas like hotel rooms and cafes, and possibly discount the coils to the mfgr as above. Still a huge capital outlay.

The problem that really sticks for me, is that the device mfgrs would ne

Except that they offer clip-on adaptors for existing electronics, so you can convert all of your electronics before the device manufacturers install the coil internally. If they could create standard pickup coils to fit into the standard size battery compartments, 2-AA, 2-AAA, 9-volt, etc., they could probably sell it to the hotels as a pad that TV remote controls and bedside alarm clocks could be placed on. Add surge protection and a normal AC outlet on the desktop part of it, and it would allow the hot

It's a pretty steep capital layout, though. And clip-on adaptors will be annoying to a ton of consumers, possibly too annoying to make it worthwhile. Takes away from the "just works" part of the product.

The problem is getting the device manufacturers to comply, since it would require capital investment for them, and would likely reduce their profits. Cell phone companies make a bundle on the chargers they sell, and most people don't bother finding a third-party vendor for accessories. New phone every 1-2 years? Don't need to get a new charger? Not good for the service carrier, and therefore not good for their phone supplier.

New phone every 1-2 years? Don't need to get a new charger? Not good for the service carrier, and therefore not good for their phone supplier.

Uhm, I think you're missing something that's, well, rather obvious: When is the last time you bought a new phone that didn't come with a charger?

If the charger costs Nokia $5 and an embedded coil costs them $1, they might just go with the coil. Saves them the cost of bundling that damn charger. Even if they were making bank selling chargers, what makes you think they

...is alot more flexible, longer, and smaller. Yes, I have to "plug it in" instead of "set it on". But my wire can be taken with me. One of them can plug into my car. both of them together are a fraction the size of this pad.And maybe I'm not getting it, but isn't that thing plugged in?!??! If I'm not mistaken, they have only replaced the plug with a plate. When I first read the article, i was excited to think someone figured out how to charge my devices anywhere... like on a trail.

I could be worrying about nothing, perhaps the power levels involved in the fields are too low to cause problems, but... do I really want to be setting my iPod or other memory-chip or mini-hard-drive device on an inductive pad?

I mean, it's fine for my toothbrush ( if a tad slow an inefficient compared to a direct cable connection )... but is that cable to my iPod really such a problem, and might it not be a tad dangerous for my precious data to place it directly on an inductive surface ?

I remember someone I worked with had one of these... the tech isn't new, but I swear there is already a product on the market that is pretty much identical to this. It was probably 2 years ago at least, and I remember she had an adapter on her cell phone and a few other devices that were charging just by sitting on the pad. I just tried searching google (haphazardly) and wasn't able to find them though...

Yeah, that was Splashpower too. This article [newscientist.com] from 21 Jan 2005 mentioned that the company "has been promising to launch its SplashPad charger for the past three years," so it's probable that you're remembering earlier coverage of the same thing.

For a mouse, I get it, it's exactly the same as the Wacom batteryless pen tables. EXACTLY. It's not new.But for other stuff, this only adds complication. I mean, you might as well just say all devices should have the same charging connector so you don't have to have multiple wall warts. That would work as well as this.

And no better.

There's still problems with voltages/power draws and trying to charge multiple devices at once.

I can think of 5 other steps which are a lot better than this one, and each is clos

So how exactly is a short range magnetic field going to give you brain cancer?

The efficiency is probably not at all bad; the magnetic field is short range and, in the absence of a receiver, the only thing in the magnetic circuit to absorb energy is the hysteresis of the inductor in the transmitter. Which, with modern ferrites, can be pretty small, unless of course they are using a purely air-cored system at the transmitter end, in which case it's tiny.

The huge potential benefit of this system is that it eliminates the second most unreliable part of electronic systems: connectors. Anyone who has worked at the sharp end of electronics knows that connectors suck, big time. Designs proliferate. There are far too many of them and they are far too unstandardised. And connectors designed to be repeatedly made and broken are the worst of the lot. Although the designs have come a long way (the fact that gigabit copper Ethernet connectors work is a small electronic miracle in itself) they are still the worst part of any system, after the batteries.So here we have a system which if widely adopted allows most of the tiny connectors used in portable devices to disappear, and possibly reduces the demands on batteries because people will find recharging easier. Those are big pluses.

I've always thought it would be cool if Apple made a completely sealed, solid-state iPod. It would need inductive charging built in, as well as wireless bluetooth headphones. I'm not sure if a standard exists for it, but there also needs to be a very short-range (i.e., through the inductive charger) high-bandwidth wireless data transfer protocol. How cool would it be to have a waterproof iPod nano? Maybe someday they'll evolve into equally slim, sealed and lightweight tablets.

So I first have to plug my iPod into a wireless charging adapter, then lay it on the "wireless charging pad" that is plugged into the wall... Wow, that is so amazing. You know what else would be sweet? If I could just place it in a cradle. Oh wait...

It would be very interesting to look at the true cost savings that *might* be able to be found from this. If you look at your average small portable consumer widget that has a connector or two, the cost of the connectors can often exceed the code of the chips.

It were wider, and able to accomodate a bunch of devices. For me, this would be:My PDA, phone, and bluetooth head set. And my wife's PDA and phone. That's five devices. A nice little "dock" by the front door where we could plop all our devices at night and grab them on the way out. Instead of a mess of transformers and a power strip to accomodate them.

Unfortunately as the article mentions, this wouldn't happen until the device makers all supported it. So they'd have to push for that first.

One good thing about wired chargers is for example when you're on your cell phone and the battery starts beeping, you just attach the wire and it charges WHILE you use the phone (i.e. have it pressed to your ear). Same thing goes with electric shavers...

None of this would work with this wireless charger. Not that I wouldn't like one laying around...

with these types of chargers is that the charging pad needs a wire connecting it to the mains. Im not saying its not a fantastic idea , but to really make benefit of these things they need to be concealed in furniture and surfaces such as desks and kitchen worktops. Integration and ubiquity is the stumbling block that we will have to overcome.In reality portable devices have already overcome the problem of needing a wire once charged we are good to go. Its TV's , consoles, vcrs, hifi's and speakers are wher

Splashpower is a really interesting company; a couple of students took developed a business plan for a competition. They won the competition and started the company off the back of it while they were still at university. They used an idea that they reasonably certain could be solved (they were both engineers) and started serious work once the funding was sorted out. They've received angel and venture funding.

Splashpads are quite interesting in that they are active devices. When you drop something onto the pad, there's some communication that goes on between the pad and the device. The pad delivers power to the right place on the pad to recharge that device, and only that place. You don't have to orientate the device correctly, and there's no contact made. You can have multiple devces recharging at once.

If you drop your keys onto the pad then they won't electrocute you when you pick them up. And they won't heat up. If you drop electronics that's not enabled onto the pad, then it won't get electrocuted either.

There is a chicken-and-egg problem. On the other hand, I would not be at all surprised to see at least one cell-phone manufacturer adopting their system, and the first step in widespread adoption is to get individual manufacturers to commit to it. They also have the advantage that past a certain penetration point it becomes a de facto standard.

There are several other competing companies. In my opinion the Splashpower system is one of the best and most likely to succeed providing they can move past initial adoption.

The one main advantage is the end of ac-dc adapters aka wall warts. This would get rid of each device needing its own proprietary power connector. I have a power strip of these just to recharge my own gadgets -- phone, gba, camera, etc.

Yes they did prove it...at least my college physics prof did by using a hypothetical line 1 foot above your head carring an impossible amout of power (1 million volts or somthing silly like that). The magnetic field generated by the line was several orders of magnitude less than the magnetic field of the earth which you are exposed to at all times.

Also the cell phone brain cancer [betanews.com] thing is becoming less and less likely.

Umm, because in AC the magnetic field is changing, which flourescent bulbs require to operate?

The earth also has an electric field of about 100 volts per meter, so the potential at your feet (if you're an average-sized adult) is different from that at your head by about 200 volts. Doesn't cause cancer.

The Earth's magnetic field is really really weak at the surface - like 30-40000 nano tesla, depending on where you are. We get exposed to many fields that are significantly stronger all the time (I definitley do - but then I work in a lab where we have several 1-2 tesla magnets going fairly often; on the otehr hand, we also have a shielded room, so I don't get exposed to Earth's magnetic field for significant portions of my day).

But two questions: First, was it alternating current? And second, how much amperage was going through the line?

Just having 1,000,000 volts above your head means nothing if there's little amperage and it's a DC power source. Alternating currents cause electromagnetic fields to propogate, and large amounts of current causes them to be more powerful. This is why you can get a flourescent tube to light up when you stand underneath high power transmission lines - The electromagnetic field from them is inducted into the tube and there is still enough power to excite the mercury atoms. Last I checked the Earth's magnetic field couldn't do something like that...

I can see why the brain cancer/cell phone controversy exists - Basically you have a very, very powerful source of EM in a concentrated spot next to your ear. The problem is that nobody can seem to prove conclusively that it causes cell mutations.

Why do people think radio waves when they hear "wireless"? Hmmm... it seems obvious to me that the trick is to induce a electric current with a magnet that is not strong enough to completely destroy the electronic components inside the device. This would work toward eliminating multiple adapters to recharge various devices and overloading wall sockets with adapters.
They aren't saying that they are recharging the devices with a high power 2.4 Ghz signal. Duh.